Method of preparing cables for multiple switchboards



UNITED STATES PATENT OFFICE.

ORO A. BELL, OF BROOKLYN, NEW YORK, ASSIGNOR TO THE WESTERN ELECTRICCOMPANY, OF CHICAGO, ILLINOIS.

METHOD OF PREPARING CABLES FOR'MULTIPLE SWITCHBOARDS.

SPECIFICATION forming part of Letters Patent No. 501,859, dated July 18,1893.

Application iiled`November'7,1892. Serial No. 451,251. (No model.)

To @ZZ whom it may con/cern.:

Be it known that I, OROA. BELL, a citizen of the United States, residingat Brooklyn, in the county of Kings and State of New York, have inventeda certain new and useful Improvement in the Manufacture of Cables forMultiple Switchboards, (Case No. 6,) of which the following is a full,clear, concise, and exact description, reference being had to theaccompanying drawings, forming a part of this specication.

My invention relates -to wiring multiple switch boards, and moreparticularly to wiring by means of separate pieces of cable.

The objects of my invention are, tirst, to prevent the loss of materialin the formation of separate cables necessitated by previous methods;and, second, to lessen the labor required in the formation of thecables.

My invention consists in removing the outside serving from a portion ofa cable, laying aside the mass of conductors thus exposed, takingup thewires individually and passing them around proper pins, binding thewires together so that they may retain their positions when removed fromthe forms, and severing the conducting wires; whereby the ends of twoseparate cables are at the same time and by one operation properlyformed for attachment to the spring jack switches.

A multiple switch board is provided with several duplicate sections,each section being composed of strips of spring jack switches, eachstrip containing usually twenty switches.

The corresponding springV j ac ks upon the dif-V ferent sections areconnected together by conducting wires and itis usual to collect all ofthe conducting wires belonging to the spring jacks of correspondingstrips into a single cable. The cables thus formed are placed at theback of the board, and in wiring by separate cables the correspondingstrips of spring jacks upon adjacent sections are connected by shortcables which are designated as separate cables. These separate cables orpieces of cable for a single series of strips are thus formed into acontinuous cable placed back of the board. The conducting wires in eachpiece of cable leave the piece when opposite the spring jack to whichthey are attached so that the extremities of each will present theappearance of wires projecting from the body of the piece at equidistantpoints along said extremities. Thus at each end for a distance equal tothe length of a strip of spring jacks the conducting wires successivelyleave the body of the piece and pass directly to the terminals of thespring jacks. It will be seen that two adjacent pieces when placed inposition will overlap at their ends throughout those portions that areopposite the strips of spring jacks to which their wires are connectedor, in other words, will overlap throughout those portions of theirextremities from which the conducting wires project. These overlappingends are either bound together or left free to suit the particularrequirements.

In multiple switch boards as now constructed, there are usually threeconducting wires passing from a spring jack upon one section to acorresponding spring jack upon the next section so thatinstead of onewire leaving the body of the cable opposite a spring jack there will bethree, and each piece of cable will contain sixty wires. Previous to myinvention these pieces of cable have been formed principally in twoways. By the rst method the piece is formed directly from single wireswhich are placed around pins so that each wire may occupy its properposition, the wires being then bound together so that they may retaintheir relative positions when removed 'from the pins.

A second method has been to take a cable of proper length,jremove theserving from the ends throughout a proper distance, take up individuallythe insulated `wires and place them around pins an'dbind them togetherin this position. The former of these methods requires a great deal oflabor, and the latter though'requiring less labor than the first isaccompanied by an unavoidable waste of material, for the wire thatprojects from the body of the piece at its extreme end determines thelength of cable that must be used, and as all other wires project fromthe piece a greater distance than the extreme wire, the ends of all mustbe cut away so that they may correspond in length to the length of theextreme wire.

To facilitate the formation of the piece by my method, the wiresbelonging to the same line are bound together in strands o r groups andeach wire is provided with a different color, as in the insulation.

My method will be more readily understood by reference to theaccompanying drawings, in which- Figure l is an yelevation of one of theduplicate forms upon which the wires are placed in the formation of theends of the cables. Fig. 2 is an end view thereof. Fig. 3 is adiagramillustrating the manner in which the individual wires are placed aroundthe pins, one wire being shown as placed around each pair of pins.

Like letters refer to like parts in the several gures.

A plate a is provided upon one side with a ange a2 by means of which itmay be secured in position. To the face of the plate a opposite to thatcarrying the flange is fastened a block b, preferably of wood, by meansof screws d d. The plate a also carries at its upper edge a series ofequidistant pins a" a', each pin bending at right angles to extend overthe block b, thus forming a receptacle for the wires between the block band the bent portions a3 of the pins. The block b is cut away at pointsbetween the fingers a a to permit of the free passage of the bindingthread between the wires of the cable and the block b. Two such formsare placed parallel, with the portions a3 of the pins extending outward,and at such a distance apart that the distance between the pins may betwice the required length of the wires that are to project from the bodyof the piece. The outer serving having been removed from a cablethroughout the necessary distance and at the proper point, a wire,determined by the color of the insulation, is taken from the mass thuslaid bare and placed around the pins marked No. l upon each form, thesepins lying directly opposite. A second Wire is placed around pins No.2,and so on with all the wires of the cable, the proper position of eachwire being determined by the color of its insulation.

In Fig. 3 the cable is shown as containing twenty wires, one wirepassing around each pair of pins. In wiring multiple switch boards, asbefore stated, there will be usually three wires passing to each springjack. These three wires are passed around the same pins. I have found itdesirable to form the two conductors constituting the metallic circuitof each line into a single strand by wrapping them with thread beforeplacing them in the cable. I prefer to leave the test wire free. Thusthere will be a strand and a single wire to'be placed around each pairof pins. All of the wires having been thus placed around the properpins, the wires-lying in the receptacle of the forms are bound togetherby threadl in such a manner that each wire may maintain its positionwhen removed from the forms. I preferably accomplish this by spirallywinding thread or twine m m around the conductors in such a manner thatthe twine may bear against each wire where it leaves the body of thecable. The wires having been thus bound together the parallel portionsof the wires running from one form to the other are cut upon a line a aand the pieces are removed from the forms. In this manner, the ends oftwo separate pieces are formed at the same time without waste ofmaterial.

To assist the eye and the memory in the selection of the proper wire foreach pin I have found it convenient to place a chart in proximity to theforms, the chart being provided, at points opposite each pin, with colors corresponding to those of the Wires that are to be placed around therespective pinsA Having thus described my invention, I claim as new anddesire `to secure by Letters Patent- 1. The method of preparing cableconnections, which consists in removing the serving from a portion of acable, separating the ex posed portion into two parts connected by wiresleaving said parts at different points, and

severingthe connecting Wires midwaybetween said parts; whereby twopieces of cable are formed with wires of equal length projecting atdifferent points along the extremities thereof, substantially asdescribed.

2. The method of preparing cable connections, which consists in removingthe serving from a portion of a cable, separating the exposed portioninto two parallel parts connected bywires passing from points along oneof said parts to points along the other, and severing said connectingwires; whereby two separate cables are formed with wires of equal lengthprojecting at different points along the extremities thereof,substantially as described.

3. The method, which consists in removing the serving from a portion ofa cable, separating the exposed wires into two groups connected by wiresleaving said groupseach at a different distance from the end thereof andin uniform order, binding together the groups thus formed by passing athread around the groups where the wires leave the same, and severingthe connecting wires; whereby two separate cables are formed with wiresof equal length projecting at different points along the extremitiesthereof, substantially as described.

et. The method of arranging the wires of cables for connectingtherewith, which consists in laying bare a portion of the cable, bendingaside the said bared portion to shorten the same, separating thedifferent wires of the cable from the mass thereof at IOO dierent pointsalong the bared `portion, and In witness whereofl hereunto subscribe mysevering Y the Wires atY equal distances from name this 13th day ofOctober, A. D. 1892. the axis of the cable; whereby two separate cablesare formed, each having its wires pro- 5 truding from its mass to equaldistances at Witnesses:

different points along its length, substantially Y MILLS H. LANDON, asdescribed. .Y Y. A. L. PALTZ.

ORO A. BELL.

